Total fat intake has also been associated with the diagnosis of asthma. N-3 fatty acids have been noted to inversely correlate with body fat, while levels of N-6 fatty acids correlated positively with body fat. Increased dietary intake of N-3 fatty acid (such as eicosapentaenoic acid) (mainly fish oils) has been generally associated with protection from asthma, while intake of N-6 fatty acids (such as linoleic acid) may increase asthma risk, although this remains controversial. Linoleic acid may act as a precursor of arachidonic acid which subsequently serves as a precursor of 4-series leukotrienes that are highly active mediators of inflammation.